• Journal of Wetlands Research
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• v.16 no.4
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• pp.379-388
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• 2014

A sewage was treated using a serially combined vertical(VFCW) and horizontal flow double media (sand and zeolite for VFCW and sand and waste oyster-shell for HFCW) reed constructed wetland(HFCW) with intermittent feeding (see Fig. 1). The sewage was fed into the reed constructed wetland for 10 minutes every 6 hours at the hydraulic load of $314L/m^2{\cdot}day$. The summarized results were as follows: pH values in the effluent depended very heavily on oyster-shell height filled in the HFCW. They were maintained at less than pH 6.24 when the height of the oyster-shell layer was 200 mm. Influent DO(oxygen demand) values(average 0.19 mg/L) were increased in the VFCW(average 7.65 mg/L) and decreased again in the HFCW(average 6.49 mg/L). They were higher in the winter than in the summer. The OTR(oxygen transfer rate) was $57.15g\;O_2/m^2{\cdot}day$ in the VFCW and $5.65g\;O_2/m^2{\cdot}day$ in the HFCW. The removal efficiency of $NH_4{^+}$-N was 80.17%(6.01 $NH_4{^+}$-N mg/L in the effluent). It was lower than that in the case where only zeolite was filled in the reed constructed wetland. But it was expected that treated sewage effluent using a double media reed constructed wetland with 300 mm zeolite layer could stably meet the Korean treated sewage effluent standard(20 mg T-N/L). Average removal efficiencies were SS 88.09%, BOD 88.12%, $COD_{Cr}$ 83.11%, $COD_{Mn}$ 85.58%, T-N 57.21%, $NH_4{^+}$-N 80.17%, T-P 86.73%. Nearly, The concentration of $NO_3{^-}$-N in the effluent of the VFCW was decreased in that of the HFCW. More than half of T-N in the effluent was $NO_3{^-}$-N(7.92 mg/L) but the concentration of $NO_2{^-}$-N in the effluent was average 0.90 mg/L. The removal efficiencies of T-P were 93.24%, 86.30% and 55.44% at the height of the oyster-shell-filled constructed wetland of 800 mm, 500 mm and 200 mm, respectively and therefore, they were proportional to oyster-shell height filled in the HFCW.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.1
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• pp.81-90
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• 2018

The purpose of this study is to evaluate the effect of downward speed limit of urban arterial roads at 29 sites in Busan Metropolitan Police Agency to reduce road traffic accidents from '10 to '15. As a result of analyzing the traffic accidents occurred for 1~3 years after the decrease in the speed limit, the number of traffic accidents decreased by 3.09% and the number of injured persons decreased by 8.76%, but the number of deaths decreased by 36.73% The results of this study are as follows. The average speed reduction rate of 6.31km/h was decreased by investigating the change of the vehicle speed before and after the downward speed limit, and the change of average speed was statistically significant in most of the sections. The rate of compliance with the speed limit increased by 10.26% p, which is considered to have greatly improved overall traffic safety. A survey conducted by residents near the target area with a lower speed limit showed that 57.9% of the respondents felt the driving speed of the vehicle was lowered. However, this project was focused on vehicles with limited speed road signs and traffic safety signs, Only 25.8% of respondents said walking safety was improved. In the future, it is necessary to consider the safety of pedestrians by improving roads around roads such as road curvature and separation. In addition, there is a clear positive result in terms of decreasing the fatal accidents in the downward speed limit zone of Busan Metropolitan Subway. However, more detailed analysis is needed for the 29 accidents. Therefore, it is expected that traffic practitioners will be able to utilize it as a basis to increase the accident reduction effect by setting an appropriate speed limit based on the easy and objective grounds.

• Journal of the Mineralogical Society of Korea
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• v.26 no.3
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• pp.151-160
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• 2013

A column experiment was carried out to study the reaction of Cr(VI) with organic carbon. Chemical analysis for the effluent collected at different times after the reaction of Cr(VI) with organic carbon in compost and SEM observation for the solid samples remaining after the reaction were conducted. Cr(VI) supplied to the column was not detected in the effluent from column at initial stage, but the concentration of Cr(VI) increased abruptly and maintained the initial supplied concentration (20 mg/kg), indicating that Cr(VI) was effectively removed from the solution at the first state. In general, the concentrations of cations and anions with the exception of $PO_4$ increased and decreased again. Considering that most of these ions were not detected or showed very low concentration, these ions are considered to originate from the organic carbon in the column. SEM observation showed that Cr was coprecipitated with Fe on the surface of organic carbon with small amount of other metals such as Mn, No, and Co. This indicated that on the reduction condition on the organic carbon, Cr(VI) was reduced to $Cr(OH)_3$ and coprecipitated with $Fe(OH)_3$, and that Fe is very important in the precipitation of Cr. After the soluble Fe and Mn are not dissolved any more, $Cr(OH)_3$ is not precipitated. Different from other ions, the concentrations of $PO_4$ decreased and increased, which was thought to be the result of the release of $PO_4$ from organic carbon and sorption on the precipitates. After the maximum sorption on the precipitates and no further release of Fe, the concentration of $PO_4$ returns to its original value measured for the ones released from the organic carbon.

• Korean Journal of Microbiology
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• v.43 no.3
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• pp.151-158
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• 2007

The possibility of inadvertent introduction of therapeutic gene expressing viral vectors has raised safety concerns about germ-line infection. Particularly, for indications such as prostate cancer and ovarian cancer, the proximity of the point of viral administration to organs of the reproductive system raises concerns regarding inadvertent germ-line transmission of genes carried by the virus vector. To evaluate the safety of in vivo adenovirus mediated gene transfer, we explored the biodistribution, persistance and potential germ-line transmission of p53-expressing adenovirus (Ad-CMV-p53). Both male and female Balb/c mice were injected with $1{\times}10^9$ PFU of Ad-CMV-p53. The PCR analysis showed that there were detectable vector sequences in liver, kidney, spleen, seminal vesicle, epididymis, prostate, ovary, and uterus. The RT-PCR analysis for detecting inserted gene, p53 showed that Ad-CMV-p53 viral RNA were present in spleen, prostate and ovary. Direct injected male and female mice of adenovirus vector into testis and ovary were mated and their of offspring were evaluated for germ-line transmission of the adenoviral vector. The PCR and RT-PCR analysis showed no evidence of germline transmission, although vector sequences were detected in DNA extracted from gonadal tissues. Real-time PCR result confirmed a significant decrease of adenovirus in gonad tissues 1 week after injection. We have also analysed the cell specific localization of viral DNA in gonad tissues by using in-situ PCR. Positive signals were detected in interstitial tissue but not in seminiferous tubule in sperm. In the case of ovary, adenovirus signal were localized to the stromal tissue, but no follicular signals were observed. Together, these data provide strong evidence that the risk of the Inadvertent germ-line transmission of vector sequences following intraperitoneal or direct injection into genito-urinary system of adenovirus is extremely low.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.2
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• pp.71-84
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• 2004

There is a growing demand for agrometeorological information that end-users can use and not just interesting information. lo achieve this, each region/community needs to develop and provide localized climate and weather information for growers. Additionally, provide tools to help local users interpret climate forecasts issued by the National Weather Service in the country. Real time information should be provided for farmers, including some basic data. An ideal agrometeorological information system includes several components: an efficient data measuring and collection system; a modern telecommunication system; a standard data management processing and analysis system; and an advanced technological information dissemination system. While it is conventional wisdom that, Internet is and will play a major role in the delivery and dissemination of agrometeorological information, there are large gaps between the "information rich" and the "information poor" countries. Rural communities represent the "last mile of connectivity". For some time to come, TV broadcast, radio, phone, newspaper and fax will be used in many countries for communication. The differences in achieving this among countries arise from the human and financial resources available to implement this information and the methods of information dissemination. These differences must be considered in designing any information dissemination system. Experience shows that easy across to information more tailored to user needs would substantially increase use of climate information. Opportunities remain unexplored for applications of geographical information systems and remote sensing in agro meteorology.e sensing in agro meteorology.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.1
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• pp.11-22
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• 2010

According to IPCC 4th Assessment Report, concentration of carbon dioxide has been increasing by 30% since Industrial Revolution. Most of IPCC $CO_2$ emission scenarios estimate that the concentration will reach up to double of its present level within 100-year if the current tendency continues. The global warming has resulted in the agro-climate change over the Korean Peninsula as well. Accordingly, it is necessary to understand the future agro-climate induced by the increase of greenhouse gases in terms of the agro-climatic indices in the Korean peninsula. In this study, the future climate is simulated by an atmosphere/ocean/land surface/sea ice coupled general circulation climate model, Pusan National University Coupled General Circulation Model(hereafter, PNU CGCM), and by a regional weather prediction model, Weather Research and Forecasting Model(hereafter, WRF) for the purpose of a dynamical downscaling. The changes of the vegetable period and the crop growth period, defined as the total number of days of a year exceeding daily mean temperature of 5 and 10, respectively, have been analyzed. Our results estimate that the beginning date of vegetable and crop growth periods get earlier by 3.7 and 17 days, respectively, in spring under the $CO_2$-doubled climate. In most of the Korean peninsula, the predicted frost days in spring decrease by 10 days. Climatic production index (CPI), which closely represent the productivity of rice, tends to increase in the double $CO_2$ climate. Thus, it is suggested that the future $CO_2$ doubled climate might be favorable for crops due to the decrease of frost days in spring, and increased temperature and insolation during the heading date as we expect from the increased CPI.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.571-584
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• 2004

It is known widely that granulosa cell apoptosis leads follicular atresia and macrophages exert their effects directly and/or indirectly from the initiation to the completion of follicular atresia by phagocytosis of apoptotic bodies and secretion of various cytokines. However, the site of initiation, propagation routes and the elimination methods of apoptotic bodies, and the time and methods of penetration of macrophages into the follicles are not known completely. Using pig(Yorkshire-breed) ovary, immunohistochemical studies with TUNEL for apoptotic bodies and pig macrophage monoclonal antibody 4E9 for macrophages, and light and transmission electron microscopic observations were performed. In the pig, follicular atresia began with the granulosa cell apoptosis, and the apoptosis of theca intema cells occured at the same time. The apoptosis of granulosa cells initiated randomly within the granulosa cell layer and propagated rapidly into the whole layer. Ultrastructura1ly, apoptotic granulosa cells showed characteristic pyknotic and deformed nucleus and intracytoplasmic vesicles. Apoptotic bodies were eliminated by intact granulosa cells and macrophages. Intact granulosa cells ingested apoptotic bodies transiently, soon after they fell into the apoptosis. Finally, apoptotic bodies and degenerated oocyte were phagocytosed by macrophages. Macrophages entered the ovarian follicle at the time of initiation of granulosa cell apoptosis, and migrated with the progression of apoptosis. By elimination of theca cells, macrophages contributed the completion of follicular atresia These results will provide valuable informations on the study of the interrelation between macrophage and ovarian follicular atresia.

• Journal of the Korean association of regional geographers
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• v.2 no.1
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• pp.25-38
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• 1996

As the proportion of women's participation in economic activities is rising, the increase of husband and wife both working and nuclear families makes children up-bringing a social problem. But many families have difficulties by the shortage of day nurseries which can solve it. As we can see in the research, the most urgent problem is the extension of nurseries in quantity. In Taegu, since it became a wide-area city, there are 473 nurseries. But in the respect of distribution, only less than 10% of Dongs have more than 7 nurseries and more than 90% of Dongs have less than 7 nurseries. Consequently nurseries are extremely insufficient. Moreover 29 Dongs don't have any nurseries at all and they take 18.6% of Dongs. The second problem is the unbalanced distribution of nurseries. West and north ward which are industrial complex and swarmed with low-income families, and Tal-sung county which is recently included in the wide-area city keenly need the establishment of nurseries. Besides, Bi-san 1 Dong and Non-gong which have only $1{\sim}2$ nurseries though they have high proportion of children and women who can be pregnant are also the areas which take precedence of nursery establishment. The third problem is that government support must be increased in the areas which have many small, petty and profit-making private nurseries so that good quality teachers can make breeding activities in nice facilities and environment. In materials which are obtained by the interviews with publich servants in charge of family welfare in some ward offices. Young and unexperienced persons who aquired certificate of qualification take day-nursery permits and run nurseries only a few months. and if the profits are insufficient, they sell the nurseries for premiums to third persons who are not qualified. Then the third managers only think of profits without thought of good quality childcare. As the result, the nurseries become asylums not nurseries. That is why the conditions of nursery establishment must be restricted to suitable scale and experienced persons. The fourth problem is that the nurseries in work places are extremely insufficient. The women who have jobs have many things to do before they go to work such as preparing meals and leaving children in the care of someone. Hence the childcare problem of working women must be solved. In nuclear families, childcare is the most serious problem for working women. The fifth one is the reduction of childcare expenses. Women must sacrifice themselves a lot to make social activities. To say nothing of physical and mental burden, they have to spend much of their salaries on childcare. And yet they don't take the benefit of good quality childcare. For the participation of women in public affairs, society must support the childcare problem to have then be devoted to their jobs without worries about their children. Therefore Taegu wide-area city must select west, north ward which are industrial complex and the low-income swarmed area before everything and establish many national, public and corporate nurseries which cost less expenses.

• Journal of the Korean association of regional geographers
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• v.3 no.2
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• pp.121-150
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• 1997

This Study puts the purpose to explicate the regionalities of land-lease farming by a comparative analisis of the five case study areas in Kungpook Province as the agricultural space system of Teagu metropolitan city. For the regional comparative analysis the province was divided into the three zones with the distance from the central city(Teagu): urban fringes, intermediate and remote zone, and then subdivided into the five regions by farming systems : horticulture, rice-farming, and dry-field farming. The data were collected from 77 land-leasing farmers by questionnaire and interview with farm managers in 5 sample villages representing the regionalities of the above five regions respectively. In spite of relatively restricted scope of the research areas, the analytical results appear remarkable regional differences in the characteristics of land-lease farming within a single agricultural space system. In the final analysis the regionalities of the five land-lease farming regions could be described respectively as follows. (1) Koryong-Gun in the inner urban fringe zone : The developing land-lease farming region of commercialized suburban horticulture with medium scale. (2) Songju-Gun in the outer urban fringe zone : The developing land-lease farming region of highly commercialized horticulture with large scale. (3) Uisong-Gun in the intermediate zone : The stagnated land-lease farming region of commercialized rice-farming with large scale. (4) Yongil-Gun in the intermediate zone : The stagnated land-lease farming region of commercializing dry-field farming with medium scale. (5) Ponghwa-Gun in the remote zone : The stagnated and delayed region in commercializing of intermountain dry-field land-lease farming with small scale. These varied regionalities resulted from the diverse spatiality as a complex of spatial orders and localities. The spatial orders in this study are frequently recognizable as a form of distance-decay, and the locality of a region is determined mostly by the its peculiarity of physical and population conditions. In the comparative analysis of the regionalities the degree of commercialization of a region is a most comprehensive and useful frame of reference because it reflects the degree of development of capitalist land-lease farming. Finally these apparent regional differentiations of land-lease farming within a agricultural space system raise the problem of impracticality of the existing uniform logic on the land-lease farming such as "large scale farms share larger part of leased farmland." This problem suggests the urgent need of reappraisal of many aspatial logics and theories on the land-lease farming.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.1
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• pp.17-24
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• 2016

Drought caused by global climate change is one of serious problems for rice cultivation. However, it was little reported the impact of drought on rice cultivation in Korea. In here, to assess impact of drought on rice varieties in Korean climate condition, growth characteristics and yield components of rice were compared on irrigated and partially irrigated rice paddy field. First, we have chosen 11 rice varieties including 'Saeilmi' and 'Shindongjin' which are widely cultivated in Korea. For partially irrigated rice paddy treatment, we have withheld irrigation from 25 days after transplanting and water supply was totally dependent on rainfall for rice cultivation. When we examined early plant height and tiller number of these varieties on partially irrigated rice paddy were reduced 1.6% to 18.4% and 10.4% to 33.1%, respectively, and these reduction rate were highly correlated with yield loss in our experimental conditions. Among rice yield components, panicle number was decreased 10.5% to 30.1% according to rice varieties and reduced panicle number was highly correlated with yield loss. Grain number per panicle, grain filling rate and 1,000 seeds weight did not have correlation with yield loss of rice varieties. These result means that growth stage, especially the tillering stage, is seriously affected by drought on rice cultivation in Korea. And we suggest that 'Saeilmi', 'Ilmi' and 'Ilpum' are good for rice cultivation on drought prone rice field in Korea.